Add new 'rate counter' implementation to libosmocore

A 'rate counter' is a counter that counts events but also keeps
track of the rate of events (per second, minute, hour and day).

'rate counters' are generally abstracted in 'rate counter groups',
which are instances of a 'rate counter group description'.  This
way we can have e.g. a description describing what kind of counters
a BTS (or TRX) has - and we can then create one instance of that
group for every BTS or TRX that exists.

1 files changed, 124 insertions, 0 deletions

diff --git a/src/rate_ctr.c b/src/rate_ctr.c
new file mode 100644
index 00000000..9b2459e8
--- /dev/null
+++ b/src/rate_ctr.c
@@ -0,0 +1,124 @@
+/* utility routines for keeping conters about events and the event rates */
+
+/* (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <stdint.h>
+#include <inttypes.h>
+#include <string.h>
+
+#include <osmocore/linuxlist.h>
+#include <osmocore/talloc.h>
+#include <osmocore/timer.h>
+#include <osmocore/rate_ctr.h>
+
+static LLIST_HEAD(rate_ctr_groups);
+
+static void *tall_rate_ctr_ctx;
+
+struct rate_ctr_group *rate_ctr_group_alloc(void *ctx,
+					    const struct rate_ctr_group_desc *desc,
+					    unsigned int idx)
+{
+	unsigned int size;
+	struct rate_ctr_group *group;
+
+	size = sizeof(struct rate_ctr_group) +
+			desc->num_ctr * sizeof(struct rate_ctr);
+
+	if (!ctx)
+		ctx = tall_rate_ctr_ctx;
+
+	group = talloc_zero_size(ctx, size);
+	if (!group)
+		return NULL;
+
+	group->desc = desc;
+	/* Generate the Group prefix from the user-specified index */
+	group->name_prefix = talloc_size(group, strlen(desc->group_prefix_fmt) + 20);
+	sprintf(group->name_prefix, desc->group_prefix_fmt, idx);
+
+	llist_add(&group->list, &rate_ctr_groups);
+
+	return group;
+}
+
+void rate_ctr_group_free(struct rate_ctr_group *grp)
+{
+	llist_del(&grp->list);
+	talloc_free(grp);
+}
+
+void rate_ctr_add(struct rate_ctr *ctr, int inc)
+{
+	ctr->current += inc;
+}
+
+static void interval_expired(struct rate_ctr *ctr, enum rate_ctr_intv intv)
+{
+	/* calculate rate over last interval */
+	ctr->intv[intv].rate = ctr->current - ctr->intv[intv].last;
+	/* save current counter for next interval */
+	ctr->intv[intv].last = ctr->current;
+}
+
+static struct timer_list rate_ctr_timer;
+static uint64_t timer_ticks;
+
+/* The one-second interval has expired */
+static void rate_ctr_group_intv(struct rate_ctr_group *grp)
+{
+	unsigned int i;
+
+	for (i = 0; i < grp->desc->num_ctr; i++) {
+		struct rate_ctr *ctr = &grp->ctr[i];
+
+		interval_expired(ctr, RATE_CTR_INTV_SEC);
+		if ((timer_ticks % 60) == 0)
+			interval_expired(ctr, RATE_CTR_INTV_MIN);
+		if ((timer_ticks % (60*60)) == 0)
+			interval_expired(ctr, RATE_CTR_INTV_HOUR);
+		if ((timer_ticks % (24*60*60)) == 0)
+			interval_expired(ctr, RATE_CTR_INTV_DAY);
+	}
+}
+
+static void rate_ctr_timer_cb(void *data)
+{
+	struct rate_ctr_group *ctrg;
+
+	/* Increment number of ticks before we calculate intervals,
+	 * as a counter value of 0 would already wrap all counters */
+	timer_ticks++;
+
+	llist_for_each_entry(ctrg, &rate_ctr_groups, list)
+		rate_ctr_group_intv(ctrg);
+
+	bsc_schedule_timer(&rate_ctr_timer, 1, 0);
+}
+
+int rate_ctr_init(void *tall_ctx)
+{
+	tall_rate_ctr_ctx = tall_ctx;
+	rate_ctr_timer.cb = rate_ctr_timer_cb;
+	bsc_schedule_timer(&rate_ctr_timer, 1, 0);
+
+	return 0;
+}